Low-income women and their infants are at risk for negative health outcomes, and the alarmingly high rate of intimate partner violence (IPV) among pregnant and post-partum women further threatens both women and infants' health. We have documented high IPV rates in our current study; a NINR-funded test of whether a social support intervention known to reduce stress helps pregnant women quit smoking. This in-progress study provides an unusual and time-sensitive opportunity to test the effects of social support intervention during pregnancy and post-delivery on important health outcomes for both women and infants. Using the sample from the current study and by over sampling, the proposed study will test the efficacy of a nurse-delivered telephone social support intervention targeted toward the mother's individual needs as well as her needs as a caregiver. We believe that intervening to reduce women's stress and depression will help them be better parents and thus raise healthier children. Pregnant women in the existing trial, who were randomized to intervention or control groups, are being recruited to continue to participate in the proposed sequential randomized controlled trial along with their newborns. There will be four groups of 80 participants each: (1) Standard Care (Control) group, (2) Social Support During Pregnancy group, (3) Social Support for 2 Years Post-Delivery group, and (4) Social Support during Pregnancy and 2 Years Post-Delivery group. Dependent measures include depression (Mental Health lndex-5), parenting stress (Parenting Stress Index Short Form), maternal-infant interactions (Parent Child Interaction Program), infant weight for length, and neurodevelopmental status (Bayley Infant Neurodevelopmental Screener). Measures will be collected at 6,12, 18, and 24 months post-delivery. Results of the proposed study will provide evidence regarding the effectiveness of a nursing intervention that targets vulnerable mothers and improves their infants' social, emotional, and cognitive well-being.